沥青混合料生产过程中，集料在滚筒中被短时间高温加热，由于钢渣集料内部组成的非均质性，可能存在开裂风险。采用A、B、C 3种钢厂的钢渣集料在（200 ~ 800 ℃）多个温度梯度条件下进行高温开裂试验，对比分析钢渣集料的开裂情况，并从钢渣不同物相高温下产生的溢出气体、热膨胀系数差异及材料内部孔隙度3个因素入手，通过X射线荧光光谱分析（X-ray fluorescence, XRF）、X射线衍射分析（X-ray diffraction, XRD）、热重-红外光谱联用分析（thermogravimetric analysis-fourier transform infrared spectroscopy, TGA-FTIR）、扫描电子显微镜微观分析（scanning electron microscopy, SEM）、体式显微镜结合开源计算机视觉库（open source computer vision library, OpenCV）图像处理分析等多分析手段对钢渣开裂机理进行研究。结果表明：钢渣中存在方铁矿和Al₃Mg₂相，相比于其他硅酸盐矿物有较高的热膨胀系数，是导致钢渣开裂的主要原因；内部具有较高的孔隙度可以吸纳内部部分热应力，进而抑制钢渣高温开裂。因此应注意钢渣集料在耐高温领域应用时可能存在的风险。

In the process of asphalt mixture production, aggregates are heated in the drum for a short time at high temperatures, which may lead to cracking due to the heterogeneity of the internal composition of steel slag aggregates. The steel slag aggregates from A, B, and C steel mills were subjected to high-temperature cracking tests under multiple temperature gradients (200 ~ 800 ℃). The cracking conditions of the steel slag aggregates were compared and analyzed. Three factors were discussed: the overflow gas produced by different phases of steel slag at high temperatures, the differences in thermal expansion coefficients, and the internal porosity of the material. The cracking mechanism of steel slag was investigated using XRF, XRD, TGA-FTIR thermogravimetric infrared spectroscopy, SEM microscopic analysis, and a type microscope combined with OpenCV computer vision image analysis. The results show that there are quartzite and Al₃Mg₂ phases in the steel slag, which have higher thermal expansion coefficients than other silicate minerals, making them the main reason for the cracking of the steel slag. The high porosity inside can absorb part of the internal thermal stress, thus inhibiting the cracking of steel slag at high temperatures. Therefore, attention should be paid to the potential risks of steel slag aggregates concerning high-temperature resistance.